Florida DEP Brings Stormwater Discussion to Naples Botanical Garden
Stormwater management may seem like a dry issue, but Southwest Florida residents’ focus on water quality is turning nutrient removal and flood prevention into everyday topics.
Adding to the ongoing dialogue, the Florida Department of Environmental Protection hosted a “monthly get-together” at the Naples Botanical Garden on Wednesday. Three presenters at the workshop discussed the challenges the region faces in stormwater management and potential solutions for removing nutrients.
Steve Preston of the Collier County Stormwater Management Team described early attempts at stormwater treatment in southwest Florida as a “ditch and drain” approach.
“Instead of just digging ditches and draining, we have the control structures in the channels to stop the water,” Preston said of today’s practice. “Think of canals as elongated reservoirs.”
Controlling water in canals through these structures provides the opportunity to control flooding, preserve wetlands and treat stormwater, he said.
Pesticides and fertilizers enter this stormwater system, adding nutrients that can lead to and exacerbate algae blooms that form in the Gulf of Mexico and the Caloosahatchee River.
Preston said Collier County sees “more problems with fertilizers and pesticides coming out of golf courses” rather than industrial parks. One solution the county has developed is neighborhood-specific management systems.
“Modern stormwater management is done in neighborhoods, and the water is then routed to another neighborhood or stored on-site for treatment,” he said.
During his presentation, Preston said that one of his favorite pieces of the stormwater management puzzle was residential rain gardens.
Some homeowners will create miniature tanks in their yard, filling it with landscaping and vegetation.
“I love rain gardens and you never see them,” Preston said. “Rain falls off the roof, down the driveway in the garden. They look great and work great.”
On a larger scale, consultant Greg Rawl said a bioreactor using woodchips is a cost-effective way to extract nitrogen from stormwater before it is reinjected into the system and eventually recharges the underground waters.
This type of system used by the City of Bonita Springs. Matt Feeney, deputy city manager of Bonita, said previous stormwater management practices were not removing enough nitrogen. He feels the city is on the cutting edge.
“We’re trying to harness a natural system that breaks down nitrogen,” Feeney said. “We are trying to exploit it by releasing it into the atmosphere.”
The bioreactor passes rainwater through a series of underground containers filled with wood chips. Nitrogen-eating bacteria live on wood chips and help remove pollutants from water.
“We think we can remove about 900 pounds of nitrogen from the system,” Rawl said. “But there is variability in flow rate and nutrient concentration to consider.”
Rawls wants to take this system and treat much larger areas in Florida. He and Feeney agree that the technology has taken off in other parts of the country, but Florida has yet to realize its potential.
Rawls’ presentation at the Garden proposed a woodchip bioreactor off the Caloosahatchee River. He said a large reactor can process 126 million gallons per day at the C-43 tank, extracting nitrogen along the way.
The bioreactor is a potential solution that municipalities can implement on a smaller scale, and Bonita Springs Mayor Peter Simmons said the stars and the moon are finally aligning for the environment.
“Please keep your foot on the gas pedal: we need to keep the heat, the pressure on the (Florida) legislature,” Simmons said. “Let’s get that money and fix our environment so we can get back to how it was before we started playing with it.”
Karl Schneider is a journalist specializing in the environment. Follow him on Facebook and Twitter: @karlstartswithkemail him at firstname.lastname@example.org